Introduction to proposed std::expected

Speaker: Niall Douglas

Audience level: Intermediate

Following on from the very successful ACCU 2017 talk "Mongrel Monads", this talk introduces the very latest post-Toronto edition of the proposed std::expected<T, E> which may make it out of the WG21 Library Evolution Working Group (LEWG) next year in time for the C++ 20 standard.

Expected is a simple vocabulary type which can be used for functional programming, fixed latency failure handling, and can increase the clarity of expression of C++ program logic.

What problems can it solve? How do you use it? Why should you use it? What should you not use it for? All these questions will be answered, and more.